Condensation product and method of producing



35 therosin without-first steaming for their removal.

Patented Apr. 26,

coNnENsA'rioN PRODUCT AND METHOD or PRODUCING Cornclis Maters, TheHague, Netherlands, as-

This invention relates signor to Hercules Powder Company,

Wilmington, Del., a corporation of Delaware No Drawing. Application July11, 1935, Serial No. 30,931

19 "Claims. (Cl. 260-3) to a condensation product and to methods ofproducing the same, more particularly it relates to formed fromextracted a condensation product pine wood pitch and an aldehyde and tomethodsior the production of this material.

Extracted pine Wood pitch, which is complex resinous material whoseexact composition is un known, comprises the residue left after theseparation of rosin, turpentine and other more valu able constituents ofpine wood. It has heretofore substantially been considered commerciallyvalueless and has accordingly ordinarily been discarded.

The pine wood pitch for use in the production of condensation productsin accordance with this invention, as has been indicated, is obtained inconnection with the p roduction of wood rosin irom pine wood. The pinewood pitch will comprise a residue low in abietic acid remaining afterthe separation of refined rosin high in abietic acid iromthe resinousmaterial obtained by extraction of pine wood with a solvent. It ischaracterized by substantial insolubility in cold petroleumhydrocarbons, but will differ somewhat in its specific characteristics,such as acid number, melting point, exact petroleumether solubility andcontent of naphtha and toluol soluble matter, de-.

pending upon the method for the recovery of rosin from pine wood used inits production. j H

As is well known, rosin pine wood by the use of may be extracted from asuitable solvent, such as hot gasoline, benzol, etcsafter steaming ofthe wood with live steam to remove volatile oils, such as'turpentine andpine oil. Again, yglatile oils,

as turpentine, and pine oil, may be extracted with Following extractionthe extract will be distilled for the removal of solvent where the woodwood pitch.

The exact properties of the pine wood pitch obtained as indicated abovewill depend upon the method used for origin al extraction from the hyde,as,for example,

wood. When the wood is steamed before solvent extraction, a pine woodpitch is obtained having somewhat different properties from thatobtained when the wood is extracted without steaming. Likewise theproperties of pine wood pitch are 5 somewhat difierent when obtained by'diiferent methods of purification of rosin. A comparison of theproperties of three pine wood pitches is given in the following table,in which Pitch A is that obtained by extraction of wood with hotpetroleum solvents subsequent to the removal of the volatile oils bysteam distillation, refining with furfura l, evaporation of the furfuraland then extraction with petroleum solvent to leave Pitch A as aresidue. Pitch B is that obtained by a benzol extraction of unsteamedwood, evaporation of the benzol, solution of the residue in not lowboiling petroleum solvent, precipitation of the Pitch B by washing withcold water, and then removal of this precipitate by filtration. Pitch Cis obtained by the evaporation of the furfural layer, after refining ofthe gasoline solution of the crude resin obtained by the benz'olextraction of pine wood.

Pitch A Pitch C The extracted pine wood pitch will be reacted inaccordance with this invention with anaideformaldehyde,paraformaldehyde, acetaldehyde, etc., to produce thecondensation product which is the subject'matter of this invention.Since extracted pine wood pitch and an aldehyde, as, for example,formaldehyde'combine readily in substantially all proportions, they maybe reacted together in any proportion.

When sufiicient quantities of the aldehyde are employed it will be foundthat the resultant condensation product-is infusible and substantiallyinsoluble. Itis preferable, however, to use such quantities of thealdehyde, as formaldehyde, that the condensation product will not reachthe infusible stage during its production, but willonly become infusibleupon continued heating at highor temperatures in admixture with, forexample, hexamethylene tetramine, as in molding. Since the proportionsof aldehyde and pine wood pitch condensation product depend upon theparticular aldehyde employed, upon the particular type of pine woodpitch, etc., and to some extent upon the conditions which obtain duringthe reaction, it is not possible to state them exactly. However, theywill usually vary from about 3% to about of aldehyde by weight per unitweight of pine wood pitch, for an aldehyde such as formaldehyde.

The extracted pine wood pitch and the aidehyde may be combined invarious ways. Where the aldehyde is a liquid or a solid it may be addeddirectly to the pine wood pitch, which may be either in solution ormolten. Formaldehyde may be added to molten or dissolved pine wood pitchin the form of its solid polymer, paraformaldehyde, or may be added to asolution of pine wood pitch as an aqueous solution. The pine wood pitch,when treated in solution, may be dissolved in an organic solventtherefor, as, for example, ethylacetat'e, alcohol, acetone, etc. Wherethe pine wood pitch is to be treated with an aqueous formaldehydesolution, it will preferably be dissolved in a water-miscible organicsolvent, as, for example, ethyl acetate, acetone, etc.

The extracted pine wood pitch may also be neutralized with an alkalimetal hydroxide or carbonate and an aqueous solution of the alkali metalsalt treated with an aqueous solution of formaldehyde. The freecondensation product may then be recovered by treatment of the mixturewith an acid, as hydrochloric acid, sulfuric acid, etc.

The reaction between the aldehyde and the pine wood pitch proceedsreadily, and takes place even at room temperatures. It will, however, bedesirable to carry out the reaction at an elevated temperature in orderto obtain a satisfactorily rapid rate of reaction. Where solvents arepresent the'reaction will usually be carried out at the boiling point ofthe solvent, altho in the case of low boiling solvents it may bedesirable to proceed under superatmospheric pressure. In general, atemperature of from about C. to about 200 C. will be found suitable forthe reaction, but it will be understood that this range by no meansindicates the limits of operability.

In some cases it will be found desirable to employ a catalyst in smallamount to accelerate the reaction, but in general the use of a catalystwill not be found necessary.

The following examples are illustrative of practical procedure in.accordance with this invention:

Example I 5 grams of paraformaldehyde were gradually added to 100 g. ofextracted pine wood pitch in a molten condition (temp. 200 C.). Theparaformaldehyde was stirred into the molten mass as added untilthoroughly incorporated in the mass. The condensation product had amelting point (drop method) of 164 C. compared to a melting point of 116C. for the pine wood pitch. The addition of 10 g. of paraformaldehyde inplace of 5 g. as above gave a condensation product having a meltingpoint of 187 C.

r Etramplev II 100 parts of extracted pinewood pitch, of the Q type ofpitch B described above, were dissolved in 100 parts of ethyl acetate.parts of a 40% aqueous solution of formaldehyde were then added to theethyl acetate solution, and the re- Example III 100 parts of extractedpine wood pitch having an acid number of 132, 10 parts sodium hydroxideand 200 parts of water were heated and stirred until complete solutiontook place. 25 parts of a 40% aqueous solution of formaldehyde were thenadded in several portions with stirring. The mixture thickened veryconsiderably. Dilute hydrochloric acid was then added to precipitate thefree condensation product, which after being washed thoroughly withwater was heated to remove the last traces of water.

The condensation product in accordance with this invention will, in itspreferred form, be just on the verge of infusibility. It will then becharacterized by being soluble in acetone and ester solvents, partiallysoluble in alcohol and ethylene dichloride, and insoluble in petroleumhydrocarbons, coal tar hydrocarbons and. turpentine. This condensationproduct may be pulverized and mixed with a small quantity ofhexamethylenetetramine to form a molding powder. This molding powder maybe substituted in whole or in part for phenol-aldehyde molding powdersand may accordingly be used in conjunction with the usual fillers, etc.in the production of molded articles, since it will cure at moldingtemperatures to an infusible product.

Thus, for example, an extracted pine wood pitch-formaldehydecondensation product preierably having a softening point (drop method)of somewhat above usual molding temperatures (about 150 C.) may befinely ground and mixed with a filler, as, for example, wood flour and aphenolic molding resin (containing some hexamethylene-tetramine). Ifdesired, additional hexamethylene-tetramine may be added. The mixturewill then be fused together on rubber rolls or other masticatingmachinery, the fused mass ground to coarse granules and then moldedunder heat and pressure at a curing temperature of about 150-165 C.

The extracted pine wood; pitch-formaldehyde condensation product mayalso be dissolved in a fused phenolic resin and the resultant massground and mixed with hexamethylene=tetramine and a filler to make amolding powder.

The softening or fusing point of the extracted pine wood pitch-aldehydeproduct for use in molding should not be substantially below the curingtemperature or the curing period will be unduly prolonged; it shouldnot, however, exceed 200 0., or the flow of the molding compoundwill beimpaired.

As fillers, asbestos, chopped cloth r other well known materials may beused. For the elimination of sticking 1% of calcium stearate may beadded.

If used in conjunction with laminated molding resins, the extracted pinewood pitch-formaldehyde product may be dissolved in phenolic laminatingvarnishes with alcohol solvent; but for the higher melting varietiesacetone solvent will suiting sheets with another resin such as aphenol-anillne-formaldehyde resin under heat and pressure The followingexamples illustrate practical molding procedure using extracted pinewood pitch-aldehyde condensation products:

Example IV An extracted pine wood pitch-formaldehyde condensationproduct having a flow point of 138 by the drop method was ball-milleddry, as follows: 1 part condensation product; 2 parts twostage phenolicmolding resin; 3 parts wood flour. This mixture was sheetecl on rolls,ground, and molded at 150 C. It was somewhat slower in cure than similarstraight phenolic molding resins.

Example V An extracted pine wood pitch-formaldehyde condensation productwhich would not soften at 150 C. but softened at 200 C. was compoundedas follows: 9 parts condensation product; 1 parthexamethyiene-tetramine; 20 parts phenolic molding resin; 30 parts woodflour. The resulting compound prepared and molded as in Example IV curedat about the same speed as phenolic molding compound.

' Example VI An extracted pine wood pitch-formaldehyde condensationproduct with a fusing point of approximately 180 C. was dissolved intwice its weight of fused phenol-aldehyde resin. The mixed resin wasthen ground with 10% of its total weight of hexamethylene-tetramine andthe resulting resin used in combination with various fillers as a hotmolding compound.

While in these examples the extracted pine wood pitch-aldehydecondensation product was used in conjunction with phenolic moldingresins, it will be understood that it may be used-with other types ofresins, as, for example, shellac, or without the addition of any'otherresin at all.

It will be understood that the details and examples hereinbefore setforth are illustrative only, and are not in limitation of the inventionherein'broadly described and claimed.

What I claim and desire to protect by Letters Patent is:

1. A condensation product formed by the reaction of a pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remaining after the separationof refined rosin high in abietic acid from the resinous materialobtained by extraction of pine wood with a solvent, with an aldehyde. I

2. A condensation product formed by the reaction of a pine wood pitch,characterized by substantiahinsolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remaining after the separationof refined rosin high in abietic acid from the resinous materialobtained by extraction of pine wood with a solvent, with formaldehyde.

'3. A condensation product formed by the reaction of a pine ;wood pitch,

characterized by I product substantial insolubility in petroleumhydrocarbons and comprising .a residue low in abietic acid remainingafter the separation of refined rosin high in abietic acid from theresinous material obtained by extraction of pine wood with a solvent,with an aldehyde, characterized by the fact that it is fusible.

4. A condensation product formed by the reaction of a pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remainlng after the separationof refined rosin high in abietic acid fromthe resinous material obtainedby extraction of pine wood with a solvent, with formaldehyde,characterized by the fact that it is fusible.

5. The method of producing a condensation product which. includesreacting a pine wood pitch, characterized by substantial insolubility inpetroleum hydrocarbons and comprising a'residue low in abietic acidremaining after the separation of refined rosin high in abietic acidfrom the resinous material obtained by extraction of pine wood with asolvent, with an aldehyde.

6. The method of producing a condensation product which includes heatinga pine wood pitch, characterized by substantial insolubility inpetroleum hydrocarbons and comprising a residue low in abietic acidremaining after the separation of refined rosin high in abietic acidfrom the resinous material obtained by extraction of pine wood with asolvent, with an aldehyde.

'7. The method of producing a condensation product which includesheating a pine wood pitch, characterized by substantial insolubility inpetroleum hydrocarbons and comprising a residue low in abietic acidremaining after the separation of refined rosin high in abietic acidfrom the resinous material obtained by extraction of pine wood with asolvent, in solution in a solvent therefor with an aldehyde.

the resinous material obtained by extraction of pine wood with asolvent, with formaldehyde.

9. The method of producing a condensation product which includes heatinga pine wood pitch, characterized by substantial insolubility inpetroleum hydrocarbons and'comprising a residue low in abietic acidremaining after the separation of refined rosin'high in abietic acidfrom the resinous material obtained by extraction of pine wood with asolvent, with formaldehyde.

10. The method of producing a condensation which includes heating a pinewood pitch characterized by substantial insolubility in petroleumhydrocarbons and comprising a residue low in abietic acid remainingafter the separation of refined rosin high in abietic acid from theresinous material obtained by extraction of pine wood with a solvent, insolution in a watermiscible solvent therefor with an aqueous solution offormaldehyde.

11. The-method of producing a condensation product which includesdissolving a pine wood pitch, characterized by substantial insolubilityin petroleum'hydrocarbons and comprising a residue low in abietic acidremaining after the separation of refined rosin high in abietic acidfrom the rennous material obtained by extraction of pine wood with asolvent, in an aqueous solution of an alkali, admixing an aqueoussolution of formaldehyde with said solution, adding an acid to saidmixture and recovering the condensation product thereby precipitated.

12. A condensation product formed by the reaction of pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remaining after the separationof refined rosin high in abietic acidfrom the resinous material obtainedby the extraction of pine wood with a solvent, with an amount of analdehyde within the range of about 3% to about 10% b weight of the pinewood pitch.

13. A condensation product formed by the .reaction of pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remaining after the separationof refined rosin high in abietic acid from the resinous materialobtained by the extraction of pine wood with a solvent, with an aldehydeat a temperature within the range of about C. to about 200 C.

14. A condensation product formed by the reaction of pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remaining after the separationof refined rosin high in abietic acid from the resinous materialobtained by the extraction of pine wood with a solvent, with an amountof formaldehyde within the range of about 3% to about 10% by weight ofthe pine wood pitch.

15. A condensation product formed by the reaction of pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue lowv in abietic acid remaining after the separationof refined rosin high in abietic acid from the resinous materialobtained by the extraction of pine wood with a solvent, withformaldehyde at a temperature within the range of about 20 C. to about200 C.

16. The method of producing a condensation product which includesheating a pine wood pitch characterized by substantial insolubility inpetroleum hydrocarbons and comprising a residue low in abietic acidremaining after the separation of refined rosin high in abietic acidfrom the resinous material obtained by extraction of pine Wood with asolvent, in solution in ethyl acetate, with an aldehyde.

17. The method of producing a condensation product which includesheating a pine wood pitch characterized by substantial insolubility inpetroleum hydrocarbons and comprising a residue low in abietic acidremaining after the separation-of refined rosin high in abietic acidfrom the resinous material obtained by extraction of pine wood with asolvent, in solution in acetone, with an aldehyde.

18. A condensation product formed by the reaction of pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remaining after the separationof refined rosin high in abietic acid from the resinous materialobtained by extraction of pine wood with a solvent, with acetaldehyde.

19. A condensation product formed by the reaction of pine wood pitch,characterized by substantial insolubility in petroleum hydrocarbons andcomprising a residue low in abietic acid remaining after the separationof refined rosin high in abietic acid from the resinous materialobtained by extraction of pine wood with a solvent, withparaformaldehyde.

CORNELIS MATERS.

